This week I had to create a sequence diagram. In the past, I’ve used MagicDraw, my favorite UML tool. However, I do not personally own a license to it, and was only fortunate to use it at a company that did. I have used ArgoUML for Use Case and Activity diagrams, but have not attempted a sequence diagram with it until this week, and found it to be difficult and limited in functionality.

So the search began for an alternative, and I was fortunate to find Sequence. Sequence is a Java GUI, which allows you type in a notation for a sequence diagram and then it creates the diagram as you type. You can save the notation as a text file, and export the diagram as a graphic.

There was a mild learning curve for the notation, but once I learned it, creating the diagram was almost as easy as just thinking about it. In the past, sequence diagrams were always difficult to create, because they were so time consuming if you had to make a correction, like adding a bunch of new classes and method calls at the top of your diagram, which causes you to have to move diagram objects around.

With this tool, you don’t even have to consider what it looks like, or where you place any of the diagram objects, or moving them around if you left something out.
You can download the jar file here, and read back to the beginning of the tool’s history. When you start the GUI, there are several examples under the Help menu to teach you the notation.